Jan Czochralski (1885-1953) - a specialist in metallurgy and inventor of the presently universal method of obtaining silicon monocrystals known as the Czochralski method (or the Czochralski process), and a method of metal recrystallisation. Having graduated from a Teacher's College he left to Berlin in 1904 where he worked on determining the quality and purity of metals and copper refining. He attended lectures on specialised chemistry in Charlottenburg at the local technical university, following which he started his own academic career. Among others, he studied the properties of light metals and in 1924 he patented what is known as metal B, a bearing alloy used in Europe and in the United States in the railway industry. Following his return to the country in 1929 he became a professor at the Institute of Chemistry at Warsaw University of Technology. The silicon monocrystals, obtained with the Czochralski method, are presently used in the production of microchips.
Ludwik Hirszfeld (1884-1954), a doctor, microbiologist and serologist, creator of the Polish school of immunology and a novel branch of science called seroanthropology. Following his medical studies in Germany he worked as assistant in the Cancer Studies Institute in Heidelberg. He also worked in the Institute of Hygiene in Zurich ( Switzerland). He studied the problems of human immunology and blood coagulability. He returned to Poland in 1918 where he carried on his research. His most outstanding achievements are his works on blood types, including the law of blood type succession and their marking (developed in cooperation with Emil von Dungern) as 0, A, B, and AB, which is in use to date, and also the marking of the Rh factor and the discovery of the reasons for the occurrence of the serological conflict. Additionally, he co-founded the National Institute of Hygiene (Państwowy Zakład Higieny) in Warsaw and the Maria Curie-Skłodowska University in Lublin (UMCS) and also established the Polish Academy of Sciences Institute of Immunology and Experimental Therapy (Instytut Immunologii i Terapii Doświadczalnej PAN) in Wrocław and the Research Centre for Pregnancy Pathology (Ośrodek Badań Patologii Ciąży). He was a university professor in Warsaw and in Wrocław.
The Polish watchmaker that gained the highest renown in the world was Antoni Norbert Patek (1812-1877). He was awarded the Golden Cross of the Virtuti Militari Order for his participation in the November uprising. Following the defeat of the insurgency, he emigrated to Prussia, and from there he went to France. After long journeys he settled in Geneva, Switzerland, where in 1839 he set up a small factory of watches in stylish casing together with Franciszek Czapek. In 1844 he met the famous French watchmaker Adrienne Philippe, inventor of the "remontoire" spring drive. A year after, the two friends together established the company Patek-Philippe, which exists to date, and launched the mass manufacture of pocket watches, followed by wrist watches later on, known for their excellent quality. Presently the company's watches are a paragon of quality and artistic design.